Flow-induced localized corrosion is a result of high shear conditions present in flow lines. The amount of corrosion that occurs is dependent on a variety of factors including the corrosiveness of the fluid flowing through the lines, the metallurgy of the line and the ability of added corrosion inhibitors to maintain adhesion to the interior of the line.
The ability of added corrosion inhibitors to maintain adhesion to the interior of the line depends on both the chemical adhesive properties of the inhibitor and the sheer stress conditions which exist inside the line. A number of products have shown promise as shear-resistant corrosion inhibitors. Included among such corrosion inhibitors are amides, quarternized amines and amide-amine salts.
While the compounds listed above have shown good adhesion characteristics, these characteristics diminish when presented with the high flow velocities present in commercial flow lines. As a result, a corrosion inhibitor with good adhesive qualities under high shear stress conditions is needed.
In U.S. Pat. Nos. 5,300,235 and 5,322,640 there has been disclosed a series of corrosion inhibitors which are acrylated tall oil fatty acid diethylenetriamine imidazolines which reflect the current understanding by those skilled in the art that to achieve satisfactory performance, such compounds must contain a hetero atom (e.g., nitrogen, oxygen or sulfur) having a nonbonding pair of electrons available for interaction with a metal surface.
While such compounds represent a significant contribution to the art of corrosion inhibition, there still remains a need for other better performing corrosion inhibitors.
It is thus an object of the present invention to provide a suitable corrosion inhibitor for inhibiting corrosion in metallic flow lines.
Another object of the present invention is to provide a process for the preclusion of corrosion in metallic flow lines.
Other aspects, objects and several advantages of the invention will be apparent from the following specification and appended claims.